Thermophiles sequences

The limited number of comparable sequences does not permit a statistical analysis for identifying thermophilic residues in archaeal proteins. Considering the data obtained for the GAPDH and PGK sequences, similar trends in the archaeal and bacterial thermoadaptation can be recognized The hydrophobic residues lie, Val, Tyr, Phe and the charged residue Glu are preferred in the thermophilic sequence, whereas the residues Asp, Asn and Cys are discriminated against [19,20]. Differences observed in other residues... 

This key enzyme of the dissimilatory sulfate reduction was isolated from all Desulfovibrio strains studied until now 135), and from some sulfur oxidizing bacteria and thermophilic Archaea 136, 137). The enzymes isolated from sulfate-reducing bacteria contain two [4Fe-4S] clusters and a flavin group (FAD) as demonstrated by visible, EPR, and Mossbauer spectroscopies. With a total molecular mass ranging from 150 to 220 kDa, APS reductases have a subunit composition of the type 012)32 or 02)3. The subunit molecular mass is approximately 70 and 20 kDa for the a and )3 subunits, respectively. Amino-acid sequence data suggest that both iron-sulfur clusters are located in the (3 subunit... 

Rhee J-K, D-G Ahn, Y-G Kim, J-W Oh (2005) New thermophilic and thermostable esterase with sequence similarity to the hormone-sensitive lipase family cloned from a metagenomic library. Appl Environ Microbiol 71 817-825. 

The thermophilic enzyme DszD from Paenibacillus All-2 has been cloned into E. coli and characterized [172], The sequence of this enzyme showed 30% similarity to the major flavin reductase of Vibrio fischeri. The optimum activity was reported to be at 45°C in resting cell cultures and 55°C in cell-free extracts. 

The only other E. coli ribosomal protein whose crystallization has so far been reported is L29 (Appelt et al., 1981). On the other hand, attempts to crystallize ribosomal proteins from the thermophilic Bacillus stearothermophilus have been more successful. Protein BL17, which according to its amino acid sequence (Kimura et al., 1980) corresponds to protein L9 from the E. coli ribosome (Kimura et al., 1982), was the first intact ribosomal protein to give crystals useful for X-ray structural analysis (Appelt et al., 1979). Several other B. stearothermophUus ribosomal proteins, namely BL6 and BL30 (Appelt eteU., 1981,1983) from the large and BS5 (Appelt et al., 1983) from the small subunit have been crystallized, and the determination of their three-dimensional structure at a resolution of better than 3 A is now in progress. Furthermore, crystals of aB. stearothermophilus ribosomal protein complex, which corresponds to the complex (L7/L12)4 LIO from E. coli ribosome, have been obtained (Liljas and Newcomer, 1981). 

The C-terminal domain (85 amino acid residues, not completely denatured at 90 °C) of the so-called a subunit of the RNAP from the extremely thermophilic eubacterium T. thermophilus (Tt) has been expressed uniformly N/ C-labelled and structurally characterized by the NMR spectroscopy. The tertiary structure of the domain, comprising a helical turn and four helices, was found to be almost identical to that of the corresponding domain from the mesophilic E. coli, despite 32% sequence homology. The interaction of the Tt domain with a variety of DNAs at 37 °C and 50 °C was investigated by chemical shift perturbation of the NMR signals and the DNA binding site was localized. ... 

Within the cellulosome complex, type I dockerin domain is responsible for incorporating its associated glycosyl hydrolase in the bacterial cellulosome via interaction with a reception domain, the cohesin domain. The three-dimensional solution structure of the 69-residue dockerin domain from the thermophilic Clostridium thermocellum (Topt = 55-65 °C) was solved by NMR and was found to consist of two Ca " -binding loop-helix motifs connected by a linker. Each Ca " -binding subdomain is stabilized by a cluster of buried hydrophobic sidechains. Recently, the NMR sequence-specific resonance assignment of type II cohesin module from C. thermocellum has been published. ... 

The influx of genomic sequence information has led to the concept of structural proteomics, the determination of protein structures on a genome-wide scale. A structural proteomic project used the sequenced genome of the thermophilic Methanobacterium thermoautotrophicum as a source of targets for structure determination.As expected, proteins from M. thermoautotrophicum possess high thermostability with a transition midpoint temperature between 68 and 98 °C. Small proteins were C- and N-labelled and their solution structures were solved using multinuclear and multidimensional NMR spectro-scopy. The project was also extended to some proteins from Thermotoga maritima ... 

Sequence comparisons may also suggest new ligands. Recently, the complete amino acid sequence for a ferredoxin from the thermophilic organism Pyrococcus furiosus was determined (Eccleston et al., 1991). All... 

Yaklichkin, S.Y. Zimina, M.S. Neumyvakin, L.V, Proline biosynthesis gene proB of thermophilic bacterium Thermus ruber cloning, sequencing, and properties of encoded y-glutamylphosphate kinase. Mol. Biol., 33, 628-635 (1999)... 

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